During the lifetime of an oil or gas well, it is typical at some point to provide selective establishment of fluid communication between the interior of a tubular string, such as a casing, liner, tubing, or the like, and the annulus surrounding the tubular string. Communication is established by creating one or more perforations tubular. It is common to use high-explosive, shaped charges to create the perforations. The shaped charges are detonated at a selected location downhole, often creating a jet of high energy plasma which penetrates the tubular string, thereby forming an opening. As hydrocarbon production increases throughout the world, certain jurisdictions discourage or prohibit the use of such explosives. Consequently, mechanical perforators have been used to perforate downhole tubulars to establish communication between the tubular interior and the surrounding annulus.
It is understood by those skilled in the art that the use of directional terms such as above, below, upper, lower, upward, downward and the like are used in relation to the illustrative embodiments as they are depicted in the figures. Where this is not the case and a term is being used to indicate a required orientation, the specification will make such clear. Upstream, uphole, downstream and downhole are used to indicate location or direction in relation to the surface, where upstream indicates relative position or movement towards the surface along the wellbore and downstream indicates relative position or movement further away from the surface along the wellbore, unless otherwise indicated.